Hitachi L200 Manual Do Utilizador

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L200 Inverter
Oper
ations
and Monitor
ing
4–51
Analog Input Operation
The L200 inverters provide for analog input to 
command the inverter frequency output value. 
The analog input terminal group includes the 
[L], [OI], [O], and [H] terminals on the 
control connector, which provide for Voltage 
[O] or Current [OI] input. All analog input 
signals must use the analog ground [L].
If you use either the voltage or current analog 
input, you must select one of them using the 
logic input terminal function [AT] analog 
type. If terminal [AT] is OFF, the voltage 
input [O] can command the inverter output 
frequency. If terminal [AT] is ON, the current 
input [OI] can command the inverter output 
frequency. The [AT] terminal function is 
covered in
. Remember that you 
must also set A001 = 01 to select analog input 
as the frequency source.
NOTE: If no logic input terminal is configured for the [AT] function, then inverter sums 
the voltage and current input to determine the desired input value.
Using an external potentiometer is a common 
way to control the inverter output frequency 
(and a good way to learn how to use the 
analog inputs). The potentiometer uses the 
built-in 10V reference [H] and the analog 
ground [L] for excitation, and the voltage 
input [O] for the signal. By default, the [AT] 
terminal selects the voltage input when it is OFF. Take care to use the proper resistance 
for the potentiometer, which is 1 to 2 k Ohms, 2 Watts.
Voltage Input – The voltage input circuit uses 
terminals [L] and [O]. Attach the signal 
cable’s shield wire only to terminal [L] on the 
inverter. Maintain the voltage within specifi-
cations (do not apply negative voltage).
Current Input – The current input circuit 
uses terminals [OI] and [L]. The current 
comes from a sourcing type transmitter; a 
sinking type will not work! This means the 
current must flow into terminal [OI], and 
terminal [L] is the return back to the transmit-
ter. The input impedance from [OI] to [L] is 
250 Ohms. Attach the cable shield wire only to terminal [L] on the inverter.
+V Ref.
A GND
Voltage input
Current input
L
H O OI
AM
+ –
4-20 mA, AT=ON
0-10 V, AT=OFF
[AT]
V/I input 
select
Freq.
setting
L
H O OI
AM
A001
1 to 2k
Ω
, 2W
L
H O OI
AM
+ –
4 to 19.6 mA DC,
4 to 20 mA nominal
0 to 9.6 VDC,
0 to 10V nominal
See I/O specs on page 
.
L
H O OI
AM
L
H O OI
AM